1. Field of the Invention
This invention relates to halogenated oxyalkylated aromatic products useful in making polyurethane foams.
2. Description of the Prior Art
When flame-retardant properties are required in polyurethane foams, it is known to use halogenated compounds and/or derivatives of phosphorus acids as active hydrogen compounds in polyurethane formulations. Often boron or antimony compounds are used in addition to said halogenated compounds to obtain improved flame-retarding properties as the result of synergism between said halogenated compounds and said boron or antimony compounds. Certain halogenated compounds, namely, monomeric materials while effective in imparting a degree of flame resistance to polyurethane plastics suffer the disadvantage of impairing the mechanical and physical properties of the polyurethane product since such materials are generally incompatible therewith and, therefore, function as diluents and fillers in the polyurethane composition.
It is known to use oxyalkylated polyols in making polyurethane foams; such polyols generally being prepared by reacting a polyhydric alcohol with an alkylene oxide in the presence of an alkaline catalyst. The alkaline catalyst which remains in the polyol is known to interfere with the reaction between the oxyalkylated polyol and the polyisocyanate used in making the polyurethane.
It is known to utilize a Friedel-Crafts catalyst such as stannic chloride to catalyze the addition of an epoxide with a polyhydric alcohol to produce a polyol. Similar catalysis occurs utilizing a phenol in place of the polyhydric alcohol as disclosed by Marple in U.S. Pat. No. 2,428,235. Conventional Friedel-Crafts catalysts are disclosed to catalyze the reaction of an aromatic or aliphatic halogenated compound with an alkylene oxide in U.S. Pat. No. 3,660,318 and to produce flame-retarding halogenated compounds useful in the preparation of polystyrene compositions exhibiting flame-retardant properties.
The use of an alkaline catalyst or an alkali salt of a pentahalophenol is disclosed as required for the production of pentahalophenoxy alkanols by the reaction of an alkylene oxide or a halohydrin according to the teachings of U.S. Pat. No. 2,416,263.
It is also known from U.S. Pat. No. 3,957,922 to prepare oxyalkylated products from a non-phenolic active hydrogen-containing compound utilizing as a catalyst a complex of a phenol and aluminum or iron.
None of the patents disclose the oxyalkylation of an aromatic hydroxyl-containing compound by the use of an epoxide compound utilizing as catalysts the compositions disclosed hereinbelow.
It is, therefore, an object of this invention to provide a new process for preparing halogenated aromatic hydroxy ethers by an oxyalkylation reaction which reaction does not require the use of the oxyalkylation catalysts of the prior art.